Data-beads(ID:7251/dat025)

3d CAD storage and representation system 

Robinson's hybrid of APT and WISP that permitted storage an manipulation of linked descriptions United Aircraft Corp Norwalk Conn 1966

Data-beads are linked lists of 3d cad descriptions
Related languages
APT => Data-beads   Extension of
WISP => Data-beads   Incorporated some features of
References:
  • Robinson, C. E. "A data structure for a computer aided design system" pp14.1-14.9 view details Abstract: United Aircraft Research Laboratories recently completed a two-year joint study with International Business Machines Corporation for investigating the application of Graphic Data Processing to 3-dimensional geometric manipulation. The joint study developed a prototype experimental system making it possible to investigate several problem areas. For example, techniques were investigated for storing within the computer 3-dimensional descriptions of objects. Crucial to such techniques is a data structure, in which is embedded information which can be quickly retrieved, thus avoiding time-consuming serial searches. Extract: 3 functions of system flow
    Slide I shows the three major functions of the system flow. The first
    function is to describe and store a description of the 3-dimensional part. A part description language, including only planes and cylinders, was sufficient for experimenting with a variety of parts. The second function of the system flow is to retrieve the stored data for calculation purposes. The calculation procedures include processing the 3-dimensional description of the part for the
    desired view, computing view oriented data (profile, projection, cross section, hidden line), and presenting the data in the form required by the display device.
    The third function of the system flow is to manipulate the information displayed on the screen. Some of the operations (such as moving information on the aisplay screen) make the system flow so that only control and output routines are involved. Other operations (such as computing new views) make the system flow so that it must retrieve the 3-D model and activate calculation procedures. Still other operations (such as changing the description of the part) make the system flow so the language input subroutines are activated.
    The data structure concerns itself with 3-dimensional geometric information and establishes a hierarchy of information for handling surfaces, lines, and points. The data structure is so organized that it is possible to readily retrieve the information after it is stored in the computer. A question that might be asked of a system is: "What is the name of the geometry displayed on the CRT and I am pointing at with the light pen?" Another question might be, "Where is the geometry whose name I am typing on the keyboard?" In either case, a data structure must be so organized that the information can be quickly accessed and retrieved.
          in [ACM/IEEE] Proceedings of the SHARE Design Automation Project Annual ACM IEEE Design Automation Conference 1965 view details